Back firing throw the carb

Energy One

SCC007

Active Member
Have there been any changes made or happened recently? Your cam/crank position sensor may be out and or your ignition out of sequence, likely trying to throw spark when intake tract is open.
 

Mikeinjersey

Well-Known Member
my bike just started to back fire threw the carb and wont start
Welcome from NJ,
What bike and engine do you have? A weak battery can cause both issues. Look for minimum 12.8 vdc not running and 14 to 14.5 while running if you do get it to run. If you were riding down the road and the charging system was not recharging the battery, when it got low it could start to backfire. After you stopped the engine it would probably not have enough juice to crank/start the engine again.
If indeed your battery has discharged your best bet would be to have it tested for a possible short. Avoid jump starting the bike if you can but if you do make sure you turn off the vehicle you are jumping from. Possible EHC damage could happen.
Come back with your findings and someone on the site can help you out. All are willing!
 

sunnyboy

New Member
Welcome from NJ,
What bike and engine do you have? A weak battery can cause both issues. Look for minimum 12.8 vdc not running and 14 to 14.5 while running if you do get it to run. If you were riding down the road and the charging system was not recharging the battery, when it got low it could start to backfire. After you stopped the engine it would probably not have enough juice to crank/start the engine again.
If indeed your battery has discharged your best bet would be to have it tested for a possible short. Avoid jump starting the bike if you can but if you do make sure you turn off the vehicle you are jumping from. Possible EHC damage could happen.
Come back with your findings and someone on the site can help you out. All are willing!
I have a 06 bigdogk9 with the 117 s@s,,,
When riding down the road the bike will start popping and then just shut down,,so I pull over and hit the start button and it starts back up again but sputters until it shuts down again
 

HMAN

I just like my Freedom
I have a 06 bigdogk9 with the 117 s@s,,,
When riding down the road the bike will start popping and then just shut down,,so I pull over and hit the start button and it starts back up again but sputters until it shuts down again
If its a carb bike, check the rubber caps on top of the carb. They will dry rot and suck air under throttle. Cheap to replace. Any auto parts store.
 

Rottweiler

Well-Known Member
I agree with Hman. When I bought my bike on the way home it started running like shit. Poping and shutting off. I got to a gas station looked over everything. One of the rubber caps fell off the top of the carb. I had nothing on me. So I looked around found a electric truck and ask for some black tape. Made a few wraps over the nipple and road it home. Had me worried because I just paid cash for it.
 

Mikeinjersey

Well-Known Member
I have a 06 bigdogk9 with the 117 s@s,,,
When riding down the road the bike will start popping and then just shut down,,so I pull over and hit the start button and it starts back up again but sputters until it shuts down again
It seems most likely a fuel/air issue but it could still be electrical. Do a few of the checks the members have suggested and if you don't find anything obvious drop the bowel and check for dirty jets and proper operation of the float. All free so it just takes a little of you time to troubleshoot if you have basic mechanical skills .
If the problem turns out to be electrical it can be a little tricky but most issues raised on this site get positive resolution without ending up going to a bike shop.
 

sunnyboy

New Member
It seems most likely a fuel/air issue but it could still be electrical. Do a few of the checks the members have suggested and if you don't find anything obvious drop the bowel and check for dirty jets and proper operation of the float. All free so it just takes a little of you time to troubleshoot if you have basic mechanical skills .
If the problem turns out to be electrical it can be a little tricky but most issues raised on this site get positive resolution without ending up going to a bike shop.
The carb is new,,,
My son had the coil off and was checking it and now he cant remember where the 3 wires go on the coil,,there is a blue one a red one and a yellow one
 
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